Waves the electromagnetic spectrum

3 marks · Normal

The wavelength of a red light wave is m. Calculate the frequency of this light.

(The speed of light in a vacuum is m/s.)

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

Hz (±20000000000000)

Must show: Correct substitution, Correct rearrangement, Correct evaluation to final answer

Also accept: Hz; Hz

Common mistakes: Incorrect rearrangement; Dividing frequency by wavelength instead of speed divided by wavelength

Show mark scheme and worked solution

Marking points

M1 · 1 mark · Correct substitution into formula or correct rearrangement for f. (follow-through)

A1 · 1 mark · Carries out correct division for frequency. (follow-through)

A2 · 1 mark · Final answer for frequency in Hz rounded appropriately (at least 2 SF). (follow-through)

Worked solution

Rearrange for frequency: